How to UV map low res textures.
I think what Duarte was trying to say is that the resolution of the textures doesn't matter for the UV layout. UV coordinates are bound to the mesh, not to the texture. 

You can create a 1024x1024 texture in blender, then resize it in whatever image manipulation software you use. For example I tend to create quite hi-res textures (4k and above) in blender, baking them and later resizing them in gimp to whatever size the final result should have. The only problem is that you are losing detail on your texture map, the UV layout fits perfectly, though.